The compositions of usual elements and rare earth elements and inclusions of corundum megacrysts related to alkali basalt in changle , shandong province , are analyzed . in the main parts of corundum megacrysts are a large number of fluid - melting inclusions , zircon , ta - columbite inclusions , and in the central crystal core are a large number of melting inclusions . the corundum megacrysts were formed in different periods and different physical chemistry conditions . the crystal core was formed in magma system , and the main parts were formed in inhomogeneously geochemical conditions in which magam and fluid phases coexisted 分析山東昌樂與堿性玄武巖有關(guān)的剛玉巨晶不同部位的常量元素、稀土元素及包裹體組成.剛玉巨晶的主體以大量流體?熔體包裹體、鋯石、鈮(鉭)鐵礦包裹體為主,而巨晶中的“晶核”部位則以大量的熔體包裹體為主,反映研究區(qū)的剛玉巨晶是在不同的階段形成的.剛玉“晶核”以及“銅皮剛玉”形成于熔體相為主的體系中,而主體剛玉則形成于熔體?流體過渡的急劇變化的不均一的地球化學(xué)環(huán)境中